Grifola frondosa, also known as Maitake, has been richly cultivated artificially in Japan for a long time and known familiarly as healthy ingredient. In recent years, the demand of Maitake comestible as supplement is increasing because the hot water extract from Maitake is considered as effective against cancer. So, growth in demand of Maitake in the form of fresh food is expected. Ease of cultivation and improvement in productivity of the mushroom are required for expedite sales.
It is critical element that the appearance, taste, preservative quality and tempting color of Grifola frondosa broth to be accepted in a market. About the broth, it is pointed out that Grifola frondosa broth is deep in color with variety.
On the other hand, Grifola frondosa had been cultivated based on wild mushroom tissue disaggregation. However, it has been so far difficult to control the postplanting environment for Grifola frondosa artificially, and mass-produce the mushroom. Thus, a new mushroom species was bred by cross-breeding techniques. For example, there has been a new variety of Grifola frondosa named ‘Hokuto NT-100’ as disclosed in U.S. Plant Pat. 17,984, which features ease of cultivating, fine flavor and improved storage stability. However, the aforementioned ‘Hokuto NT-100’ still has room for improvement in coloration and keeping quality.